JPS61229108A - Self-standing unmanned vehicle - Google Patents

Abstract

PURPOSE:To measure the distance from a short-distance object so as to make a self-standing unmanned vehicle stronger to physical impacts, by burying a transmitting loudspeaker and receiving microphone in the main body of the unmanned vehicle to a depth corresponding to the pulse width of an ultrasonic pulse. CONSTITUTION:Ultrasonic waves radiated from a buried transmitting loudspeaker A go to the outside through a space produced when the speaker A is buried and reflecting waves of the ultrasonic waves by means of outside objects are inputted in a receiving microphone B through a space produced when the microphone B is buried. Therefore, the propagating distance of the ultrasonic is made longer by the length of the space when compared with the case where the loudspeaker A and microphone B are fitted to the side wall of the unmanned vehicle and measurement of any short-distance objects becomes possible.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an autonomous unmanned vehicle that measures the distance to an external object using ultrasonic waves, and particularly relates to an ultrasonic transmitting speaker (transmitting transducer) and a receiving microphone. (Conventional technology) The second factor is a side view of the configuration of a conventional self-supporting unmanned vehicle (hereinafter referred to as unmanned vehicle). In the figure, l is the main body of the unmanned vehicle.

2 is a wall, 3F1 is a floor, and C is an ultrasonic transmitting circuit that generates an ultrasonic frequency signal, modulates the signal as a carrier wave with a pulse waveform, and sends it to a transmitting speaker (transmitting transducer).
At the same time, it outputs a signal and outputs a timing signal of the timing to the signal processing circuit E. A is a transmitting speaker, which receives an ultrasonic pulse signal from the transmitting circuit C and emits the ultrasonic pulse signal to the outside world as an ultrasonic wave. B is a receiving microphone, and the ultrasonic waves emitted from transmitting speaker A are objects in the outside world.

For example, it receives ultrasonic waves that hit a wall 2, etc., are reflected, and return. Dtlf ultrasonic pulse signal receiving circuit.

The ultrasonic wave signal received by the receiving microphone is input, amplified and shaped, and a comparator is used to check whether the signal is the same as the signal emitted from the transmitting speaker A. If it's a signal.

The port E that outputs the timing signal at the received timing to the FI processing circuit E is a signal processing circuit, and the transmitting circuit C
The difference time t3 from the timing of ultrasonic emission inputted from
= t2-tl is measured, and from this the distance between the unmanned vehicle and an object in the outside world is calculated. In FIG. 3, the transmitting speaker A and the receiving microphone B in FIG. 2 are shared by one transducer F, and when transmitting with the selector switch S, the switch 8t? When tilting the transmitter circuit to the C side to emit and receive ultrasonic waves.

The switch S is turned to the receiving circuit side for reception.

[Problem that the invention seeks to solve]

When switching between transmission and reception using the changeover switch S as shown in FIG. Therefore, measurement at a close distance corresponding to the length of propagation time of the pulse width of the ultrasonic pulse signal is impossible.

In addition, even if transmitting speaker A and receiving microphone B are installed as shown in Figure 2 above, it is theoretically possible, but in reality, acoustic noise and circuit noise may be mixed in when the distance is close. , measurable. As described above, conventional unmanned vehicles have the disadvantage that it is impossible to measure close distances. The present invention aims to eliminate such conventional drawbacks.

[Means for solving problems]

FIG. 1 is a diagram showing an example of the configuration of an unmanned vehicle according to the present invention.

1 to 3 in the figure. A-11ii shows the same part as in the case of the second factor. As can be understood by comparing FIG. 1 with FIG. 2, in the past, the transmitting speaker A and the receiving microphone B were mounted on the side wall of an unmanned vehicle, but in the present invention, they are embedded inside the unmanned vehicle body and are opened through an opening. In this case, the depth of embedding may be determined by considering the first order. ■If the pulse width of the ultrasonic pulse is large, the thicker it is, the deeper it will be embedded. In this case, if the Hals medium is thick, it will be reflected by hitting an object in the outside world, and when the leading edge of the pulse width returns, the trailing edge of the pulse width will still be emitted. This is because the switching becomes impossible and the noise is generated, making it impossible to measure the close distance. ■In actual cases, to improve measurement accuracy,
- It does not only emit pulses once, but also emit pulses at a certain period in succession.The higher the pulse frequency at this time, the greater the effect; Don't go home yet - this is a method that will cause confusion when the next pulse is emitted. ■As the distance increases, the angle of reflection on the external object decreases, and as the distance decreases, the angle of reflection on the external object decreases. The larger the distance, the more difficult it is for reflected waves to be input to the receiving microphone B installed at a fixed position. Therefore, the distance and the directivity characteristics (reflection angle) of the ultrasonic waves must be made to closely match. Including.

For this reason, the embedding depth, which is related to the distance, must be determined in consideration of the ultrasonic characteristics.

[Effect]

The ultrasonic waves emitted from the embedded transmitting speaker A go out to the outside world through the carefully constructed embedded space.
Further, the nine reflected waves reflected by external objects are input into the receiving microphone B through the space created by the embedded receiving microphone B. Therefore, compared to the conventional case, the ultrasonic wave propagates [li] longer by the space distance that can be embedded. With this method, the present invention has made it impossible to measure objects at close range.

Since it appears to be far away, it can be measured.

[Effects of the invention] ■As mentioned above, it becomes possible to measure distances to objects at close range,
At the same time, (1) the outer panel of an unmanned vehicle has no protruding parts, making it more resistant to physical shocks, and the same effect is produced as if the unmanned vehicle itself had become substantially smaller.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of the configuration of an autonomous unmanned vehicle according to the present invention. Figure 2 is a side view of the configuration of a conventional autonomous unmanned vehicle, and Figure 3 is where the transmitting speaker A and receiving microphone B in Figure 2 are located. It is a connection side view when one transducer F is used for both purposes.

Claims (1)

[Claims] 1. A transmitting circuit (C) and a transmitting speaker (A) in an autonomous unmanned vehicle
. An ultrasonic sensor device consisting of a receiving microphone (B), a receiving circuit (D), and a signal processing circuit (E) is attached, and the transmitting circuit (C) generates an ultrasonic signal and the microphone (B) transmits it to the outside world. An ultrasonic wave is emitted, the ultrasonic wave hits an object in the outside world, is reflected, and is received by the receiving microphone (B) and the receiving circuit (D), and is received by the signal processing circuit (E). In an autonomous unmanned vehicle that determines the distance between an autonomous unmanned vehicle and an object in the outside world by measuring the time from emission to reception of ultrasonic waves, the transmitting speaker (A) and the receiving microphone (B) are installed. An autonomous unmanned vehicle that is embedded and installed inside an autonomous unmanned vehicle.